Type-writing machine.



W. F.HBLMOND. TYPE WRITING MACHINE.

APPLIOITION FILED JULYIB. 1905.

Mpg} fiwgfman LVWW.

PATBNTED MAY 22, 1906.

UNITED s'rA r s PATENT OFFICE.

U NQERWOOD TYPEWRITER COMPANY, OF NEW YORK, N. Y., A

CORPORATION OF NEW JERSEY.

TYPE-WRITING MAOHiNE.

Specification of Letters Patent.

I Patented May 22-, 1905.

Application filed J c1318, 1905: Borllffl'o- 376,299.

To. all whom it may concern:

Be it known that 1, WILLIAM F. IIELMOND, a citizen of the United States, residing in Hartford, in the county of Hartford and State of Connecticut, have invented certain new and useful Improvements in Type ivriting Machines, of which the following is a specification.

This invention relates to the iettenfeeding meei'ianisni of type-writing machines, and particulariy to the device which checks the escnpemcnt-wheei against undue backward rotation when the carriage-rack is released therefrom. p

The oh'cct of the invention is to prevent wear upon the teeth of the esca Lament-wheel, such as occurs in machines in w liGll said teeth force the check out of their way, and to proyide against i'aulty operation of the mechanism. 7

I provide, in addition to the usual feedingdogs, a back-check, which is caused to reciprocate simultaneously with the feedingdogs into and out of the esca ement-teeth,sa1d back-check being operate b y the finger -keys instead of by the teeth of the escapcmentwheel, thus reducing somewhat the amount of ower required to drive the carriage and ma ing a more certain operation of the backcheck. I also provide the check with a pivot, so that in case durin ra machine the check sfiou d on a e the wron tooth of the escapementwhee the latter wi vibrate the check out of the way.

In the accompanying drawings, Figure l is 9. pers ective view of the escapoment mechanisrno thewell-known Underwood typewritin machine, showing my improvements 9. piic thereto. Fig. 2 1s a rear elevation of t 6 same.

The carriage 1 of the Underwood machine is springpro elled by means of a. strap 2 and provided wit a rack 3, which meshes with a. pinion 4, the rack bcin I releasabie from the pinion in order to enable quickly forward. Connected to the pinion is an esca ement-wheei or curved neck 5 Upqn a me or 6 are mounted spacing and detent dogs -i and of the escapement-whel 5 and alternately into and outof the escapcment-wheei and carriage advance step by step under the influence of the spring )iil operation of the k the carriage to run I of the haekecheck 22coiiidmg witil'the wheeliit has inst escaped, this 8, which move transvereeiy notches therein to let the mechamsm 2. An abutment 9, carried upon a table or frame 10, which rcciprocetes hack ward and forward at each key-stroke, enages the rocker 6 to vibrate the same in one ireotion, white :2. spring 11 returns ihe frame 30 to normal position. A spring 1'2 is also provided {or the escapcsnenhdogs. At its rear end the frame 19 ls provided, with arms 13 14, whereby it is pivoteliy mounted upon the upper ends of a pair of uprl ht rock-arms 15 15, connected by a rock-shaft 17-, hurt? u on pivots 18. I hen a key is dcpresse t e frame moves back, together with the arms 13 14 and the rock-arms 15 16, as well as the dog-rocker 6, and when the key is reiieved from pressure ali of said parts move forward to normal position, As so far do scribed the parts are in common use in said Underwood type-writing machine.

Upon the 11 right rock-arm 16 I fix an arm 19, having a iagonal extension 20, directed up toward the escapement-Wheel 5. Upon the free end of the extension 20 I pivot at 21 a. back-check pawi 22, which normally stands; between adjoining teeth 23 of thecscapemcn wheel 5 to prevent undue backlash of the latter whenever the rack is released from the pinion 4'. The arm 20 being fixed to the rock-arm 16 vibrates baokwardiy, to other with the frame 10 and the, dog-rack er 6., whereby the back-check 22 is carried hidewise out of the nth of the teeth 23 of the escepenient-whee thus avoiding the necessity of being forced out by the action of said escapement-teeth themselves and a -oiriing weer upon said eseapenienoteeth. Upon the reiicf of the key from pressure the parts all return to normal position, togetherwith the arm 20 and the back-ch6ck '22, the latter never needing to be touched by the escapem'ent teeth. Y

When the machine is operated at high speed, and particulargrif the eseapemenidogs 7 8 are not adjusts with preci'eeness lIRiH f tively to one another, is some liebihtr check is so pivoted that the escapement-tooth will simply turn it upon the pivot and pa e as the escapement-tooth 23 passes.

"eratin {lecte'cl the feeding-dogs into and out of the'series of es'capement-teeth, said pawl' pivoted and eld when engaged by the escapemerit-teeth in advancing and thereby forced out of theirpath; means by. This vibration of the back-check is illustrated in dotted lines at Fig. 2. A weighted arm 24, formed upon the backcheck, Wlll restore the same to'n'ormal condition as-soon A stop 25 upon the arm 24 catches over'the top edge of the arm 20 to arrest the downward movement of 24, while a similar sto 26 engages the under edge of. the arm 20 tolimit the upward vibration of arm 24.

Having thus described my cla1m- 1. In a type-writer letter-feeding mechanism, the combination with a carria e, a series of escapement-teeth, and feedingogs cooperatirlg therewith, of a back-check pawl con necte to reciprocate simultaneously with invention, 1

thefeedi ng-dogs into and out of the series of escapement-teeth, said pawl -pivoted and adapted to yield when engaged by the escape- Inent-teeth in advancing and thereby forced out of their path. v a

a 2. Ina ty e-writer letter feeding mechanism," the comlvination with acarria 'e, a series of escapement-teeth, and feeding ogs'cooptherewith, of a back-check pawl conto reciprocate simultaneously with adapted to yi being provided for;

restorin the back-check pawl to normal position a'ter such actionb' the escapementteeth.

3. In a type-Writer letter-feeding mechanism, the combination with a carria e, a series of escapement-teeth and feedingogs cooperating therewith, of an arm vibrating transversely of the series of escapement-teeth at the feeding operation, a back-check pawl pivoted upon said arm and adapted to yield when engaged by theescape'ment-teeth in advancing and thereby forced out of their ath,

and means restoring said pawl to norma condition.

4. In a type-writer letter-feeding mechanism, the combination with a series of escapement-teeth and feedin -dogs cooperating therewith, of an arm vibrating transversel of the series of escapement-teeth at the fee ing operation, a back-check pawl ivoted upon said arm and adapted'to yield .w an enga ed by the escapement-teeth in advancing and thereby forced'out of their path; sai back-check pawl having a avity-arm for gestoring it to normal condition, and stops said ack eheck pawlup'onits pivot.

. WILLIAM F. HELMOND. Witnesses;

Ema-J; .MANNIN'G, Fnnnamox E. LEWIS.

provided forlimiting the vibration of 

